1. Field
The field of the presently disclosed subject matter is weld elements that are designed to facilitate the assembly of components of a vehicle when using welds, such as projection welds, to connect components of the vehicle. In particular, the disclosed subject matter is directed to a weld element that includes various sealing structure that prevents contaminants from passing through the weld element. The weld element can also include structures that allow venting of any outgassing that occurs during the welding procedures to ensure quality of the weld seal.
2. Brief Description of the Related Art
Weld nuts and bolts can be assembled to other metal parts such as body panels on a vehicle by projection welding. Projection welding allows for the production of a part with few heat surface marks on one side of the panel. One or more projections can be provided on the weld nut or bolt, and electrodes contoured to the finished part can be used in the welding process to achieve the desired results.
Flanged weld nuts that include integral washers have been used for assembling components such as vehicle components assembled to the body or frame of the vehicle. The flange of the flanged weld nut can bridge an oversized hole in a workpiece or body member to which another component is to be attached. Flanged weld nuts can be pre-attached to the workpiece or body member so that the body member can be bolted to something else. This method of attachment is useful in joining vehicle body parts and facilitates the assembly of the vehicle.
Projection welding is a common practice for joining a weld nut or other fastener to a metal sheet or other workpiece. Integral, discrete projections on a metal sheet contacting side of the weld nut provide fusible metal for the weld. Two counter-acting welding electrodes with flat contact surfaces hold the weld nut and workpiece together at a joining region with the projections on the weld nut pressing against the surface of the workpiece. A controlled electrical power source delivers a pulse of high amperage AC (or rectified AC) current through the facing electrodes, through the interposed weld nut, and the workpiece. Typically a 60 Hertz welding current is applied for several cycles of electrical current application (i.e., a fraction of a second). Although the entire nut and underlying workpiece area are heated, the higher density and momentary current flow through the projections tend to selectively melt the projections. When the current flow is stopped, the melt solidifies and the projections are fused to the workpiece.
Weld nut welding processes can use a copper welding electrode with a flat, full faced electrode tip to engage the top of the weld nut. The flat welding electrode tip is large enough to fit weld nuts of different sizes and is effective in applying clamping pressure on the flat surface of the top of the nut's barrel. A counteracting electrode can be provided to engage the opposite side of the workpiece.